Well I'll be a Monkeys (*&*&

I didn't think it was possible so I just had to ask the rest of the airhead drivers. The bike is a 74 R60/6, been riding it since mid eighties, do my own maintenance. A few weeks back I had to replace my transmission input drive seal and clutch because it got wet from the leaking seal. When I opened the servicing plug for the tranny an excessive amount of fluid came out, I didn't think anything of it at the time, thinking only I must have over serviced it. Well for the last two weeks since the maintenance I've been noticing the same thing happening again. When I open the filler plug on the tranny, fluid just gushes out (and yes its gear oil) keep in mind I've been servicing this motorcycle for over twenty years now and I have never seen this before. Well I also noticed the drive shaft needs constant servicing and to check for leaks in the seals I check the final drive. its fluid level is where its always been, no changes. So the only thing I can assume is the drive shaft is leaking fluid into the transmission . How can that be?? The drive shaft grades down to the final drive, even when I sit on the bike. I have been told its impossible...but yet here I am looking at a scenario that shouldn't happen. I am draining the same amount out of the tranny that is missing in the drive shaft???? Go figure, will someone please enlighten me!!! Sorry for the grammer, as I am doing this on a dumbass phone under a bridge hiding from the rain, its bad enough here in Houston with dumb drivers, now enter rain, not a good mix.

Hell of a message from a phone! Wow!! Nice thumbs...

I have heard people say that fluid can work back forwards...under what circumstances, I'm not sure or don't remember. My thinking is that the speedo bolt, which has the hole through the middle, isn't open anymore. This hole lets the transmission breathe as things heat up and cool down. It seems to me that if this hole were blocked, then upon cooling, there might be a tendency to try and suck fluid from the driveshaft. What if the oil is pushed through the seal into the driveshaft when hot, then when cool, it's like a siphon back into the transmission?

I does sound like the output shaft seal is also compromised.

How old is the output shaft seal if its new is it installed backwards? If its old sounds like it needs replaced.

Check that the transmission vent - the axial hole in the bolt that holds the speedometer cable and ground cable in place - is clear. The seal will sometimes retain oil in the transmission if pressurized, but will allow oil to be sucked in past the seal with the vacuum when a hot transmission cools if that vent hole is clogged.

Did you figure out the cause of this yet?

Sorry fellas, I was called out on a trip, was in NYC for a few days... did see a R60/5 on 5th Ave and 25-27th street area the guy was riding it almost everyday and it showed 70,000+ miles on the od, how cool is that. Nope I have not had a chance to look at it, hopefully by this weekend I should find something out.

Alright, Ill go from here.

I finally had some down time yesterday. I pulled the breather bolt from the tranny, it was open no clogs. I went a little further and pulled out the speedo drive gear to check for blockage, none to be found. Put everything back together. I drained some more tranny fluid, by placing the bike on the side stand and place a drain pan under the filler plug of the tranny and open it up to let the excess amount flow out, note the amount. I checked the drive shaft and sure enough it has lost the same amount of fluid again. However, instead of putting more back in I drain to see what's left and sure enough I have plenty. So I put that amount (not the amount from the tranny) back in the final drive and I go to bed. Today I drive to work as usual and as soon as I get here I open the tranny filler hole, alasssss no excessive fluid mmmmmmm lets wait and check again after it cools, so after three or four hours I check and the level is good, no excessive fluid as before . So I am assuming two things here, 1. I was over servicing the drive shaft. or 2. I must have did something to the breather area in the tranny. I'll keep an eye on things to make sure it settles.
Any who, what is the proper amount for the drive shaft any ways?

I think the book calls for 150cc but in reality, 100cc or even down to 50cc is all that is necessary. Do you remember how much you have been putting in? On my /7, I drain the driveshaft and then refill with 100cc. I don't recall actually measuring how much comes out...I should probably do that sometime, just to see how much residual remains.

Hey Kurt, Yea I don't really remember how much it was. I used to service it to just to the top of the drive shaft using a scribe as a measuring device, however a few years ago (for some stupid reason, probably lose of memory) I started to fill it up until the bottom of the filler plug. I just never realized it was that much, I guess I was over servicing it by 100-130CC almost double it required.